1. Field of the Invention
The present invention relates generally to oil filter devices and, more particularly, to oil filter devices having a filtering action that is magnetically enhanced.
2. Description of the Prior Art
The use of a magnet array to enhance the filtering properties of oil filter devices is well known in the art. In this respect, throughout the years, a number of innovations have been developed by the present inventor herein relating to magnetically enhanced oil filter devices, and the following U.S. patents are representative of some of those innovations: U.S. Pat. Nos. 6,426,000, 6,649,053, and 6,758,969.
More specifically, each of U.S. Pat. Nos. 6,426,000 and 6,649,053 discloses a magnet array which employs top and bottom horizontally oriented shunt magnets and top and bottom shunt members in contact with the top and bottom horizontally oriented shunt magnets. To reduce the need for horizontally oriented shunt magnets, it would be desirable if a magnet array did not need both top and bottom shunt magnets.
Furthermore, since the bottom portion of a magnet array is in closer proximity to the oil being filtered than the top portion of the magnet array, and since it would be desirable to reduce the number of horizontally oriented shunt magnets, it would be desirable if the top portion of the magnet array, the portion farthest from the oil being filtered, does not employ a horizontally oriented shunt magnet.
U.S. Pat. No. 6,758,969 discloses a magnetically enhanced oil filter apparatus in which internal walls direct oil flow toward a magnet array located on the top of the apparatus. In addition, the oil filter material occupies space that is closely adjacent to the magnet array. As a consequence, some of the oil filter material obstructs the flow of oil to some portions of the apparatus which are adjacent to the magnet array. In this way, the efficiency of the magnet array is impeded. In this respect, it would be desirable if a magnetically enhanced oil filter apparatus were provided which does not have oil filter material obstructing the flow of oil to some portions of the apparatus which are adjacent to the magnet array.
Another feature of U.S. Pat. No. 6,758,969 is the apparent lack of an internal pressure relief valve that would relieve an excessive build up of oil pressure if the oil filter material becomes excessively clogged. In this respect, it would be desirable if a magnetically enhanced oil filter apparatus were provided which accommodates the presence of an internal pressure relief valve to relieve excessive internal oil pressure.
Thus, while the foregoing body of prior art indicates it to be well known to use magnetic enhancement of oil filtering, the prior art described above does not teach or suggest a magnetically enhanced oil filter apparatus which has the following combination of desirable features: (1) provides a magnet array that does not need both top and bottom shunt magnets; (2) has a top portion of the magnet array, the portion farthest from the oil being filtered, that does not employ a horizontally oriented shunt magnet; (3) does not have oil filter material obstructing the flow of oil to some portions of the apparatus which are adjacent to the magnet array; and (4) accommodates the presence of an internal pressure relief valve to relieve excessive internal oil pressure. The foregoing desired characteristics are provided by the unique magnetically enhanced oil filter apparatus of the present invention as will be made apparent from the following description thereof. Other advantages of the present invention over the prior art also will be rendered evident.